Flexible display having a crack suppressing layer

ABSTRACT

A flexible display may suppress a generation of cracks in an inorganic layer and suppress the spread of cracks. A flexible display includes a flexible substrate and an inorganic layer formed on the flexible substrate. A display unit is formed on the inorganic layer. The display unit includes a plurality of pixels. Each pixel includes an organic light emitting diode. A thin film encapsulation layer covers the display unit. A crack suppressing layer is formed along the edge of the flexible substrate. The crack suppressing layer is disposed on the inorganic layer at an exterior side of the thin film encapsulation layer.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 to Korean PatentApplication No. 10-2013-0096161 filed in the Korean IntellectualProperty Office on Aug. 13, 2013, the disclosure of which isincorporated by reference herein in its entirety. This is a reissueapplication from U.S. Pat. No. 9,472,779, issued on Oct. 18, 2016, whichclaims priority under 35 U.S.C. § 119 to Korean Patent Application No.10-2013-0096161 filed in the Korean Intellectual Property Office on Aug.13, 2013, the disclosure of which is incorporated by reference herein inits entirety.

(A) Technical Field

The present disclosure relates to a flexible display, and morespecifically, to a flexible display device.

(B) Discussion of Related Art

A flat panel display may be formed of a substrate and a display unitincluding a plurality of pixels formed on the substrate. The flat paneldisplay may have a bending characteristic when the substrate is formedof a flexible substrate such as a plastic film and not a rigid substratesuch as glass. The flexible display device may be a self-emissiveorganic light emitting diode (OLED) display.

The flexible display device may be manufactured through a process inwhich a plurality of display units and a plurality of thin filmencapsulation layers are formed on a flexible mother board. An upperprotection film and a lower protection film may be layered in theflexible mother board. The plurality of thin film encapsulation layersmay be separated to individual flexible displays by cutting between theplurality of thin film encapsulation layers. The upper protection film,the lower protection film, and the flexible mother board may be cutthrough a press method using a cutting knife.

A strong press cutting force may be transmitted to the flexible displayand at substantially the same time a bending force may be applied to theflexible display during the cutting process.

SUMMARY

Exemplary embodiments of the present invention provide a flexibledisplay that may minimize a generation of cracks during a cuttingprocess and prevent a failure such as, for example, panel contraction bypreventing a spread of cracks toward a thin film encapsulation layer.

A flexible display according to an exemplary embodiment of the presentinvention includes a flexible substrate and an inorganic layer formed onthe flexible substrate. A display unit is formed on the inorganic layer.The display unit includes a plurality of pixels. Each pixel includes anorganic light emitting diode. A thin film encapsulation layer covers thedisplay unit. The crack suppressing layer is disposed on the inorganiclayer at an external side of the thin film encapsulation layer.

The crack suppressing layer may be configured to contact the edge of theflexible substrate. The crack suppressing layer may be disposed at anuppermost edge of the flexible substrate.

The inorganic layer may include a barrier layer, a buffer layer, a gateinsulating layer, and an interlayer insulating layer.

The barrier layer, the buffer layer, the gate insulating layer, and theinterlayer insulating layer may cover an entire top surface of theflexible substrate.

The barrier layer and the buffer layer may cover an entire top surfaceof the flexible substrate. The gate insulating layer and the interlayerinsulating layer may be disposed at an inner side of the cracksuppressing layer. The gate insulating layer and the interlayerinsulating layer may be formed at a constant distance from the edge ofthe flexible substrate.

The crack suppressing layer may be formed at an inner side of theflexible substrate. The crack suppressing layer may cover a portion ofthe inorganic layer. The inorganic layer may include a barrier layer, abuffer layer, a gate insulating layer, and an interlayer insulatinglayer.

The barrier layer and the buffer layer may cover an entire top surfaceof the flexible substrate. The gate insulating layer and the interlayerinsulating layer may be disposed at an inner side of the cracksuppressing layer at a constant distance from the edge of the flexiblesubstrate.

The barrier layer, the buffer layer, the gate insulating layer, and theinterlayer insulating layer may be formed at an inner side of the cracksuppressing layer between the edge of the flexible substrate and thecrack suppressing layer.

The crack suppressing layer may include an organic material.

The display unit may include a planarization layer and a pixel defininglayer. The crack suppressing layer may include a same material as atleast one of the planarization layer and the pixel defining layer.

The crack suppressing layer may include a first layer including a samematerial as the planarization layer and a second layer including a samematerial as the pixel defining layer.

The crack suppressing layer may include a UV curable resin and/or athermosetting resin.

According to exemplary embodiments of the present invention, a loss ofencapsulation function of the thin film encapsulation layer due to thespread of cracks may be prevented. Panel contraction and display failuremay be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the inventive concept will become moreapparent by describing in detail exemplary embodiments thereof, withreference to the accompanying drawings in which:

FIG. 1 is a top plan view of a flexible display according to anexemplary embodiment of the present invention;

FIG. 2 is a partial cross-sectional view, cut along the line II-II ofFIG. 1;

FIG. 3 is a schematic cross-sectional view showing a method ofmanufacturing the flexible display according to an exemplary embodimentof the present invention;

FIG. 4 is a partially enlarged cross-sectional view of a flexibledisplay according to an exemplary embodiment of the present invention;

FIG. 5A and FIG. 5B are partially enlarged cross-sectional views of aflexible display according to an exemplary embodiment of the presentinvention; and

FIG. 6 is a partially enlarged cross-sectional view of a flexibledisplay according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present invention will be described more fully hereinafter withreference to the accompanying drawings, in which exemplary embodimentsof the invention are shown. As those skilled in the art will realize,the described embodiments may be modified in various different formswithout departing from the spirit or scope of the present invention.

It will be understood that when an element such as a layer, film,region, or substrate is referred to as being “on” another element, itmay be directly on the other element or intervening elements may bepresent.

FIG. 1 is a top plan view of a flexible display according to anexemplary embodiment of the present invention, and FIG. 2 is a partialcross-sectional view of FIG. 1 taken along the line II-II.

Referring to FIG. 1 and FIG. 2, a flexible display 100 according to anexemplary embodiment of the present invention includes a flexiblesubstrate 10, a display unit 20 formed on the flexible substrate 10, anda thin film encapsulation layer 30. The thin film encapsulation layer 30may cover the display unit 20. The display unit 20 may include aplurality of pixels PE. The display unit 20 may display an image with acombination of light emitted from each of the plurality of pixels PE.Each pixel PE may include a pixel circuit and an organic light emittingdiode (OLED) 40. Light emitted from the OLED 40 may be controlled by thepixel circuit.

The flexible substrate 10 may include a plastic film such as, forexample, a polyimide or a polycarbonate. When the plastic film has ahigher moisture transmission rate and higher oxygen transmittance thanglass, transmittance of external moisture and oxygen through theflexible substrate 10 may be blocked. A barrier layer 11 and a bufferlayer 12 may be formed on the flexible substrate 10.

The barrier layer 11 may be formed of a plurality of inorganic layers,and for example, a silicon oxide layer and/or a silicon nitride layer.The plurality of inorganic layers may be alternately and repeatedlystacked. When the barrier layer 11 has a lower moisture transmissionrate and lower oxygen transmittance than the flexible substrate 10 thatmay be formed of the plastic film, moisture and oxygen transmittedthrough the flexible substrate 10 may be suppressed from permeating intothe display unit 20.

The buffer layer 12 may be an inorganic layer, and may include, forexample, a silicon oxide or a silicon nitride. The buffer layer 12 mayprovide a flat surface for forming the pixel circuit. The buffer layer12 may suppresses permeation of moisture and foreign particles into thepixel circuit and the OLED 40.

A thin film transistor 50 and a capacitor (not shown) may be formed onthe buffer layer 12. The thin film transistor 50 may include asemiconductor layer 51, a gate electrode 52, a source electrode 53,and/or a drain electrode 54.

The semiconductor layer 51 may include a polysilicon or oxidesemiconductor. The semiconductor layer 51 may include a channel area 511in which impurities are not doped, a source area 512 and a drain area513 in which impurities are doped at respective sides of the channelarea. When the semiconductor layer 51 is formed of the oxidesemiconductor, a separate protective layer for protecting thesemiconductor layer 51 may be added.

A gate insulating layer 13 may be formed between the semiconductor layer51 and the gate electrode 52. An interlayer insulating layer 14 may beformed between the gate electrode 52 and the source and drain electrodes53 and 54. The gate insulating layer 13 and the interlayer insulatinglayer 14 may be inorganic layers.

The thin film transistor 50 shown in FIG. 2 may be a driving thin filmtransistor. The pixel circuit may include a switching thin filmtransistor (not shown). The switching thin film transistor may be aswitching element that selects a pixel for light emission. The drivingthin film transistor may apply power for light emission of the selectedpixel to the corresponding pixel.

In FIG. 2, the thin film transistor 50 may be formed with a top gatestructure, for example, but the structure of the thin film transistor 50is not limited thereto. The pixel circuit may include three or more thinfilm transistors and two or more capacitors.

A planarization layer 15 may be formed on the source and drainelectrodes 53 and 54. The planarization layer 15 may include an organicmaterial. The planarization layer 15 may include, for example, an acrylresin, an epoxy resin, a phenolic resin, a polyamide resin, and thelike. The planarization layer 15 may have a via hole that partiallyexposes the drain electrode 54. The OLED 40 may be formed on theplanarization layer 15.

The OLED 40 may include a pixel electrode 41, an organic emission layer42, and a common electrode 43. The pixel electrode 41 may be formed ineach pixel. The pixel electrode 41 may be connected with the drainelectrode 54 of the thin film transistor 50. The common electrode 43 maybe formed throughout a display area DA of the flexible substrate 10. Thepixel electrode 41 may be surrounded by the pixel defining layer 16. Thepixel defining layer 16 may partition pixel areas. The organic emissionlayer 42 may be formed on the exposed pixel electrode 41. The pixeldefining layer 16 may be formed of an organic material such as, forexample, a polyimide.

The organic emission layer 42 may be a red emission layer, a greenemission layer, or a blue emission layer. The organic emission layer 42may be a single white emission layer. The organic emission layer 42 mayhave a layered structure of a red emission layer, a green emissionlayer, and/or a blue emission layer. When the organic emission layer 52has the layered structure, a color filter (not shown) may be included.

One of the pixel electrode and the common electrode may be a holeinjection electrode (anode) and the other may be an electron injectionelectrode (cathode). Holes injected from the anode and electronsinjected from the cathode may be combined in the organic emission layer42 to generate excitons. Light may be emitted while the excitonsdischarge energy.

A hole injection layer and/or a hole transport layer may be disposedbetween the anode and the organic emission layer 42. An electroninjection layer and/or an electron transport layer may be disposedbetween the cathode and the organic emission layer 42. The holeinjection layer, the hole transport layer, the electron transport layer,and the electron injection layer may be formed on the entire displayarea DA of the flexible substrate 10.

One of the pixel electrode 41 and the common electrode 43 may be formedof a metal reflective layer and the other may be formed of asemi-transmissive layer or a transparent conductive layer, for example.Light emitted from the organic emission layer 42 may be reflected by themetal reflective layer. Light emitted from the organic emission layer 42may then be emitted to the outside through the semi-transmissive layeror the transparent conductive layer. When light is emitted by thesemi-transmissive layer, light emitted from the organic emission layer42 may be partially reflected to the reflective layer such that aresonance structure is formed.

The thin film encapsulation layer 30 may encapsulate the OLED 40 fromthe external environment. The encapsulation layer 30 may reducedeterioration of the OLED 40 due to moisture and oxygen. The thin filmencapsulating layer 30 may have a configuration in which a plurality oforganic layers and a plurality of inorganic layers are alternatelystacked one by one.

The organic layer of the thin film encapsulating layer 30 may include apolymer. The organic layer of the thin film encapsulating layer 30 maybe a single layer or a stacked layer formed of, for example,polyethylene terephthalate, a polyimide, a polycarbonate, an epoxy,polyethylene, and/or a polyacrylate. The inorganic layer of the thinfilm encapsulating layer 30 may be a single layer or a stacked layercontaining a metal oxide or a metal nitride. For example, the inorganiclayer may contain any one of SiNx, Al₂O₃, SiO₂, and TiO₂.

The flexible substrate 10 may include a display area DA where thedisplay unit 20 and the thin film encapsulation layer 30 are disposed.The flexible substrate 10 may include a pad area PA disposed at anexterior side of the thin film encapsulation layer 30. Pad electrodes(not shown) connected with the pixel circuit may be disposed in the padarea PA. The pad electrodes may be electrically connected with a chip onfilm 61 attached to the pad area PA or a flexible printed circuit board,for example. In FIG. 1, reference numeral 62 denotes an integratedcircuit chip installed in the pad area PA.

In the flexible display 100, the inorganic layer 19 including thebarrier layer 11, the buffer layer 12, the gate insulating layer 13, andthe interlayer insulating layer 14 may be formed over the entire uppersurface of the flexible substrate 10. The thin film encapsulation layer30 may be disposed at an inner side separated by a constant distancefrom the edge of the flexible substrate 10 such that the inorganic layer19 is exposed to the outside of the thin film encapsulation layer 30.The thin film encapsulation layer 30 may be disposed at an inner side ofthe flexible substrate 10. There may be a gap of about 600 μm to about700 μm between the thin film encapsulation layer 30 and the flexiblesubstrate 10.

FIG. 3 is a schematic cross-sectional view showing a method ofmanufacturing the flexible display according to an exemplary embodimentof the present invention.

Referring to FIG. 3, the flexible display 100 may be manufacturedthrough a process in which a plurality of display units 20 and aplurality of thin film encapsulation layers 30 are formed on a flexiblemother board 110. An upper protection film 65 and a lower protectionfilm 66 may be layered in the flexible mother board 110. The flexiblemother board 110 may be cut into individual flexible displays by cuttingbetween the plurality of thin film encapsulation layers 30. The upperprotection film 65 and the lower protection film 66 may be removed fromthe separated flexible displays.

The upper protection film 65 and the lower protection film 66 mayinclude a plastic film and/or an adhesive layer, for example.

When cutting the flexible mother board 110, a wheel cutting method or alaser cutting method used to cut a rigid substrate such as glass, forexample, need not be used. For example, when the wheel cutting method isused, the upper protection film 65 and the lower protection film 66 maybe torn during the cutting process. For example, when the laser cuttingmethod is used, the OLED 40 may be damaged in an initial stage due toheat from laser irradiation. The flexible mother board 110 may be cutthrough a press method using a cutting knife 67.

A cutting force of about 5 tons to about 15 tons may be applied to theflexible mother board 110 during the cutting process so that stress isconcentrated to the inorganic layer 19 disposed in the cutting line CL.The cutting knife 67 may penetrate the upper protection film 65 anddirectly cut the inorganic layer 19. A bending stress may be generatedin the flexible mother board 110. An inorganic layer 19 that is brittlemay be damaged, thereby generating cracks.

Referring to FIG. 1 to FIG. 3, the flexible display 100 according toexemplary embodiments of the present invention includes a cracksuppressing layer 70. The crack suppressing layer 70 may be formed alongthe edge of the flexible display 10 on the inorganic layer 19 at anexternal side of the thin film encapsulation layer 30. The cracksuppressing layer 70 may contact an edge the flexible substrate 10corresponding to the cutting line CL. The crack suppressing layer 70 maybe disposed at the uppermost edge of the flexible substrate 10.

In the external side of the display area DA, the crack suppressing layer70 may contact the thin film encapsulation layer 30 or may be disposedat a desired distance from the thin film encapsulation layer 30. In theexternal side of the pad area PA, the crack suppressing layer 70 may bea desired width along the edge of the flexible substrate 10.

The crack suppressing layer 70 may include an organic material that isthe same organic material as is included in at least one of theplanarization layer 15 and/or the pixel defining layer 16. The cracksuppressing layer 70 may include a first layer 71. The first layer 71may include the same material as the planarization layer 15. The cracksuppressing layer 70 may include a second layer 72. The second layer 72may include the same material as the pixel defining layer 16. The widthof the first layer 71 may be equal to or greater than the width of theplanarization layer 15, and the width of the second layer 72 may beequal to or greater than the width of the pixel defining layer 16.

The crack suppressing layer 70 may be formed at the same time as theplanarization layer 15 and the pixel defining layer 16. An additionalpattern mask need not be used to form the crack suppressing layer 70.The first layer 71 and the planarization layer 15 may be formed at thesame time, and the second layer 72 and the pixel defining layer 16 maybe formed at the same time.

When the crack suppressing layer 70 formed of an organic material isdisposed at the uppermost edge of the flexible substrate 10, the cuttingknife 67 may first contact the crack suppressing layer 70 rather thanthe inorganic layer 19 in the cutting process shown in FIG. 3. The cracksuppressing layer 70 may function as a buffering member for theinorganic layer 19 disposed below the crack suppressing layer 70. Thecrack suppressing layer 70 may function as a buffering member at themoment the cutting knife 67 contacts that crack suppressing layer 70 orthe inorganic layer 19, and generation of cracks in the inorganic layer19 may be minimized.

Two organic structures (e.g., the crack suppressing layer 70 and theflexible substrate 10) may support the inorganic layer 19 at the edge ofthe flexible substrate 10 that corresponds to the cutting line CL. Thespread of the cracks to the thin film encapsulation layer 30 through theinorganic layer 19 may be prevented. A loss of an encapsulation functionof the thin film encapsulation layer 30 due to the spread of cracks maybe prevented. Panel contraction and a display failure may be prevented.

The crack suppressing layer may include a UV curable resin or athermosetting resin used as a sealant. For example, the UV curable resinmay be a polyester resin containing a radical initiator, an epoxy resin,a urethane resin, a polyether resin, or a polyacryl resin. For example,the thermosetting resin may be an epoxy resin, an amino resin, a phenolresin, or a polyester resin.

For example, the sealant may be more resistant to an external impactthan the planarization layer 15 and the pixel defining layer 16. Thecrack suppressing layer 70 formed of the sealant may reduce the impactapplied during the cutting process.

FIG. 4 is a partially enlarged cross-sectional view of a flexibledisplay according to an exemplary embodiment of the present invention.

Referring to FIG. 4, a flexible display 200 according to an exemplaryembodiment of the present invention is the same as the flexible displayof the exemplary embodiment of FIGS. 1 and 2, except that a part of aninorganic layer 19 is disposed at an inner side of the flexiblesubstrate 10 with a gap between the edge of the flexible substrate 10and the inorganic layer 19. The same reference numerals may be used forthe same components as those of the exemplary embodiment of the presentinvention of FIGS. 1 and 2.

A barrier layer 11 and a buffer layer 12 may be formed over an entiretop surface of the flexible substrate 10 and may block a permeation ofmoisture and oxygen to the flexible substrate 10. A gate insulatinglayer 13 and an interlayer insulating layer 14 may function as aninsulation layer. Edges of the gate insulating layer 13 and theinterlayer insulating layer 14 may be partially eliminated. The gateinsulating layer 13 and the interlayer insulating layer 14 may bedisposed at an inner side of the crack suppressing layer 70. The gateinsulating layer 13 and the interlayer insulating layer 14 may bedisposed at a constant distance from the edge of the flexible substrate10.

The edge of the gate insulating layer 13 and the edge of the interlayerinsulating layer 14 may be disposed between the edge of the flexiblesubstrate 10 and a thin film encapsulation layer 30. The cracksuppressing layer 70 may contact the top surface of the exposed bufferlayer 12 and a part of an upper portion of the interlayer insulatinglayer 14.

As the thickness of the inorganic layer 19 is decreased at the edge ofthe flexible substrate 10 corresponding to a cutting line CL, theflexible display 200 according to an exemplary embodiment of the presentinvention may suppress generation of cracks during a cutting process andsuppress spread of the cracks during a process after the cuttingprocess.

FIG. 5A and FIG. 5B are partially enlarged cross-sectional views of aflexible display according to an exemplary embodiment of the presentinvention.

Referring to FIG. 5A and FIG. 5B, a flexible display 300 according to anexemplary embodiment of the present invention is the same as theflexible display of the exemplary embodiment of FIGS. 1 and 2, exceptthat a crack suppressing layer 70 is formed at an inner side of theflexible substrate 10 with a gap from the edge of a flexible substrate10 to a side of the crack suppressing layer 70. The same referencenumerals may be used for the same components as those of the exemplaryembodiment of FIGS. 1 and 2.

When a gap between the cutting line CL and the crack suppressing layer70 is relatively small and the flexible substrate 10 is disposed at aninner side of the crack with a constant gap between the edge of theflexible substrate 10 and the crack suppressing layer 70, a cuttingknife 67 may contact the crack suppressing layers 70 at both sides ofthe cutting line CL during a cutting process. The crack suppressinglayer 70 may function as a buffering member of the inorganic layer 19disposed therebetween and minimize the generation of cracks in theinorganic layer 19. The crack suppressing layer 70 may minimize thegeneration of cracks in the inorganic layer 19 at a moment that thecutting knife 67 contacts the crack suppressing layer 70.

In the flexible display 300 according to an exemplary embodiment of thepresent invention, a part of the inorganic layer 19, for example, a partof a gate insulating layer 13 and a part of an interlayer insulatinglayer 14, may be eliminated and the gate insulating layer 13 and theinterlayer insulating layer 14 may be formed at an inner side of thecrack suppressing layer 70 between the edge of the flexible substrate 10and the crack suppressing layer 70. The thickness of the inorganic layer19 may decrease at the edge of the flexible substrate 10 so that thegeneration of cracks and the spread of the cracks may be suppressed.

FIG. 6 is a partially enlarged cross-sectional view of a flexibledisplay according to an exemplary embodiment of the present invention.

Referring to FIG. 6, a flexible display 400 according to an exemplaryembodiment of the present invention is the same as the flexible displayof the exemplary embodiment of FIGS. 5A and 5B, except that the entireinorganic layer 19 is formed at an inner side than a crack suppressinglayer 70 between the edge of a flexible substrate 10 and the cracksuppressing layer 70. The same reference numerals may be used to referto the same components as those of the exemplary embodiment of FIGS. 5Aand 5B.

A part of the entire inorganic layer 19 may be eliminated and theinorganic layer 19 may be disposed at an inner side of the cracksuppressing layer 70 between the edge of the flexible substrate 10 andthe crack suppressing layer 70. The flexible substrate 10 may be exposedaround a cutting line CL, and the crack suppressing layer 70 may cover aside surface and a part of a top surface of the inorganic layer 19.

According to the exemplary embodiment of FIG. 6, the inorganic layer 19may be eliminated around the cutting line CL, and the cutting knife 67need not contact the inorganic layer 19 during a cutting process. Thecutting knife 67 may contact the flexible substrate 10 and the cracksuppressing layers 70 at both sides of the cutting line CL. Thegeneration of cracks in the inorganic layer 19 during the cuttingprocess may be minimized and the spread of the cracks after the cuttingprocess may be substantially suppressed. The flexible display accordingto exemplary embodiments of the present invention may prevent damage toa thin film encapsulation layer 30 by cracking, and substantiallyprevent a loss of an encapsulation function of the thin filmencapsulation layer 30.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetail may be made therein without departing from the spirit and scopeof the present invention.

What is claimed is:
 1. A flexible display, comprising: a flexiblesubstrate; an inorganic layer disposed on the flexible substrate,wherein the inorganic layer comprises a barrier layer, a buffer layer, agate insulating layer, and an interlayer insulating layer; a displayunit disposed on the inorganic layer, wherein the display unit includesa plurality of pixels, each pixel thereof including an organic lightemitting diode; a thin film encapsulation layer covering the displayunit; and a crack suppressing layer formed along an edge of the flexiblesubstrate, wherein the crack suppressing layer is disposed directly onthe interlayer insulating layer of the inorganic layer at an exteriorside of the thin film encapsulation layer, wherein the crack suppressinglayer is configured to contact the edge of the flexible substrate, andthe crack suppressing layer is disposed at an uppermost edge of theflexible substrate.
 2. The flexible display of claim 1, wherein thebarrier layer, the buffer layer, the gate insulating layer, and theinterlayer insulating layer cover an entire top surface of the flexiblesubstrate.
 3. The flexible display of claim 1, wherein the barrier layerand the buffer layer cover an entire top surface of the flexiblesubstrate, and the gate insulating layer and the interlayer insulatinglayer are disposed at an interior side of the crack suppressing layer,and the gate insulating layer and the interlayer insulating layer aredisposed at a constant distance from the edge of the flexible substrate.4. The flexible display of claim 1, wherein the barrier layer and thebuffer layer cover an entire top surface of the flexible substrate, andthe gate insulating layer and the interlayer insulating layer aredisposed at an inner side of the crack suppressing layer at a constantdistance from the edge of the flexible substrate.
 5. The flexibledisplay of claim 1, wherein the barrier layer, the buffer layer, thegate insulating layer, and the interlayer insulating layer are formed atan inner side of the crack suppressing layer between the edge of theflexible substrate and the crack suppressing layer.
 6. The flexibledisplay of claim 1, wherein the crack suppressing layer comprises anorganic material.
 7. The flexible display of claim 6, wherein thedisplay unit comprises a planarization layer and a pixel defining layer,and the crack suppressing layer comprises a same material as theplanarization layer or the pixel defining layer.
 8. The flexible displayof claim 7, wherein the crack suppressing layer comprises a first layerincluding a same material as the planarization layer and a second layerincluding a same material as the pixel defining layer.
 9. The flexibledisplay of claim 6, wherein the crack suppressing layer comprises atleast one of a UV curable resin and a thermosetting resin.
 10. A displaydevice, comprising: a flexible substrate; an inorganic layer disposed ona portion of the flexible substrate, wherein the inorganic layercomprises a barrier layer, a buffer layer, a gate insulating layer, andan interlayer insulating layer, and wherein a portion of the flexiblesubstrate is not covered by the inorganic layer; a thin filmencapsulation layer disposed over a display unit, wherein the displayunit is disposed on the inorganic layer; and a crack suppressing layerformed over the portion of the flexible substrate not covered by theinorganic layer, wherein the crack suppressing layer is disposeddirectly on the inorganic layer and the crack suppressing layer covers aside portion of the inorganic layer comprising the barrier layer, thebuffer layer, the gate insulating layer and the interlayer insulatinglayer, and a top portion of the inorganic layer, wherein the cracksuppressing layer is configured to prevent cracks from forming in theinorganic layer during a cutting process, wherein the crack suppressinglayer is configured to contact the edge of the flexible substrate, andthe crack suppressing layer is disposed at an uppermost edge of theflexible substrate.
 11. The display of claim 10, further comprising anupper protection film disposed on the thin film encapsulation layer. 12.The display of claim 10, wherein the crack suppressing layer comprises afirst layer and a second layer.
 13. The display of claim 10, wherein thecrack suppressing layer comprises a UV curable resin or a thermosettingresin.
 14. The display of claim 10, wherein the crack suppressing layercomprises a sealant.
 15. A flexible display, comprising: a flexiblesubstrate; an inorganic layer disposed on the flexible substrate,wherein the inorganic layer comprises a barrier layer, a buffer layer, agate insulating layer, and an interlayer insulating layer; a displayunit disposed on the inorganic layer, wherein the display unit includesa plurality of pixels, each pixel thereof including an organic lightemitting diode; a thin film encapsulation layer covering the displayunit; and a crack suppressing layer formed along an edge of the flexiblesubstrate, wherein the crack suppressing layer is disposed directly onthe interlayer insulating layer of the inorganic layer at an exteriorside of the thin film encapsulation layer, and wherein the cracksuppressing layer is formed at an inner side spaced apart from the edgeof the flexible substrate, and the crack suppressing layer covers aportion of the inorganic layer.
 16. The flexible display of claim 15,wherein the barrier layer and the buffer layer cover an entire topsurface of the flexible substrate, and the gate insulating layer and theinterlayer insulating layer are disposed at an inner side of the cracksuppressing layer at a constant distance spaced apart from the edge ofthe flexible substrate.
 17. The flexible display of claim 15, whereinthe barrier layer, the buffer layer, the gate insulating layer, and theinterlayer insulating layer are formed at an inner side of the cracksuppressing layer between spaced apart from the edge of the flexiblesubstrate and the crack suppressing layer.
 18. A flexible display,comprising: a flexible substrate; a transistor disposed on the flexiblesubstrate and including a semiconductor layer, a gate electrode, asource electrode, and a drain electrode; a first inorganic layerdisposed between the semiconductor layer and the flexible substrate; anorganic light emitting diode disposed on the transistor and electricallyconnected to the transistor; a second inorganic layer disposed on thesemiconductor layer; a third inorganic layer disposed between the firstinorganic layer and the flexible substrate; a fourth inorganic layerdisposed between the second inorganic layer and the semiconductor layer;a thin film encapsulation layer covering the organic light emittingdiode; and a crack suppressing layer disposed directly on the secondinorganic layer and along an edge of the flexible substrate, wherein atleast a portion of the crack suppressing layer and at least a portion ofthe thin film encapsulation layer are in contact with the secondinorganic layer, and the crack suppressing layer includes a firstportion in contact with a lateral side of the second inorganic layer, asecond portion in contact with an upper side of the second inorganiclayer, and a third portion in contact with the upper side of the firstinorganic layer.
 19. The flexible display of claim 18, wherein: theorganic light emitting diode includes a first electrode electricallyconnected to the transistor, an organic emission layer disposed on thefirst electrode, and a second electrode disposed on the organic emissionlayer, the flexible display further comprising: a first organic layerdisposed between the second inorganic layer and the organic lightemitting diode; and a second organic layer disposed between the firstorganic layer and the second electrode and including an opening thatoverlaps at least a portion of the first electrode, and the cracksuppressing layer comprising a same material as at least one of thefirst organic layer and the second organic layer.
 20. The flexibledisplay of claim 19, wherein: a height of the crack suppressing layer issmaller than a height of the thin film encapsulation layer withreference to the flexible substrate.
 21. The flexible display of claim20, wherein: the crack suppressing layer is spaced apart from the edgeof the flexible substrate by a constant distance.
 22. The flexibledisplay of claim 18, wherein: the organic light emitting diode includesa first electrode electrically connected to the transistor, an organicemission layer disposed on the first electrode, and a second electrodedisposed on the organic emission layer, the flexible display furthercomprising: a first organic layer disposed between the second inorganiclayer and the organic light emitting diode; and a second organic layerdisposed between the first organic layer and the second electrode andincluding an opening that overlaps at least a portion of the firstelectrode, and at least a portion of the first organic layer is incontact with the second inorganic layer.
 23. The flexible display ofclaim 22, wherein: a height of the crack suppressing layer is smallerthan a height of the thin film encapsulation layer with reference to theflexible substrate.
 24. The flexible display of claim 23, wherein: thecrack suppressing layer is spaced apart from the edge of the flexiblesubstrate by a constant distance.
 25. The flexible display of claim 18,wherein: a height of the crack suppressing layer is smaller than aheight of the thin film encapsulation layer with reference to theflexible substrate.
 26. The flexible display of claim 18, wherein: thecrack suppressing layer is spaced apart from the edge of the flexiblesubstrate by a constant distance.
 27. The flexible display of claim 18,wherein: a total thickness of the first inorganic layer and the secondinorganic layer decreases at the edge of the flexible substrate.
 28. Theflexible display of claim 18, wherein: the organic light emitting diodeis disposed on the second inorganic layer; and a total thickness of thefirst inorganic layer and the second inorganic layer at the edge of theflexible substrate is smaller than a total thickness of the firstinorganic film and the second inorganic film in a display area of theflexible substrate where the organic light emitting diode is disposed.29. The flexible display of claim 18, wherein: the organic lightemitting diode is disposed on the second inorganic layer; the secondinorganic layer and the fourth inorganic layer extend from a displayarea of the flexible substrate where the organic light emitting diode isdisposed to the edge of the flexible substrate, and edges of the secondinorganic layer and the fourth inorganic layer are disposed at aconstant distance from the edge of the flexible substrate.
 30. Aflexible display, comprising: a flexible substrate; a transistordisposed on the flexible substrate and including a semiconductor layer,a gate electrode, a source electrode and a drain electrode; a firstinorganic layer disposed between the semiconductor layer and theflexible substrate; an organic light emitting diode including a firstelectrode electrically connected to the transistor, an organic emissionlayer disposed on the first electrode, and a second electrode disposedon the organic emission layer; a second inorganic layer disposed on thesemiconductor layer; a first organic layer disposed between the secondinorganic layer and the organic light emitting diode; a second organiclayer disposed between the first organic layer and the second electrodeand including an opening that overlaps at least a portion of the firstelectrode; a third inorganic layer disposed between the first inorganiclayer and the flexible substrate; a fourth inorganic layer disposedbetween the second inorganic layer and the semiconductor layer; a thinfilm encapsulation layer covering the organic light emitting diode; anda crack suppressing layer disposed directly on the second inorganiclayer and along an edge of the flexible substrate, wherein at least aportion of the first organic layer is in contact with the secondinorganic layer, and the crack suppressing layer includes a firstportion in contact with a lateral side of the second inorganic layer, asecond portion in contact with a upper side of the second inorganiclayer, and a third portion in contact with the upper side of the firstinorganic layer.
 31. The flexible display of claim 30, wherein: a heightof the crack suppressing layer is smaller than a height of the thin filmencapsulation layer with reference to the flexible substrate.
 32. Theflexible display of claim 30, wherein: the crack suppressing layer isspaced apart from the edge of the flexible substrate by a constantdistance.
 33. The flexible display of claim 30, wherein: the secondinorganic layer and the fourth inorganic layer extend from a displayarea of the flexible substrate where the organic light emitting diode isdisposed to the edge of the flexible substrate, and edges of the secondinorganic layer and the fourth inorganic layer are disposed at aconstant distance from the edge of the flexible substrate.